Ever been on a machine that was ailing and just wouldn't respond? As soon as you're root, lower the priority of the offending process ID(s) (in this example, 1103) by using the 'renice' command:

# renice -19 1103

If you've munged your template1 database, you can rebuild it from the template0 database.

First, you must set the datistemplate attribute of template1 to false so we can drop it:

xinu=# UPDATE pg_database SET datistemplate = false WHERE datname = 'template1';
UPDATE 1
xinu=# DROP DATABASE template1;
DROP DATABASE

Next, re-create template1 using template0 as a template:

xinu=# CREATE DATABASE template1 WITH TEMPLATE = template0;
CREATE DATABASE

Then restore the datistemplate attribute of template1:

xinu=# UPDATE pg_database SET datistemplate = true WHERE datname = 'template1';
UPDATE 1

If you see the following when trying to load a newly transplanted database, it may be due to a difference in architecture (32-bit vs. 64-bit):

FATAL:  incorrect checksum in control file.

The moral is: never do a direct copy of the data directory. It isn't considered good practice.

If you have a database mytemplate that you'd like to use as a template, update its datistemplate attribute in the pg_database relation:

UPDATE pg_database SET datistemplate = 't' WHERE datname = 'mytemplate';

Then you can use it as a template when creating other databases:

CREATE DATABASE otherdb TEMPLATE mytemplate;